Core-unit for vehicular-radiator-type heat exchanger and protective shields therefor



Sept. 22, 1964 w. v. ASTRUP CORE-UNIT FOR VEHICULAR-RADIATOR-TYPE HEAT EXCHANGER AND PROTECTIVE SHIELDS THEREFOR Filed Sept. 24, 1962 INVENTOR. WILLIAM V. ASTRUP ATT Y United States Patent Office 3,149,667 Patented Sept. 22., 1964 3,149,667 CORE-UNIT FOR VEHICULAR-RADIATOR-TYPE HEAT EXCHANGER AND PROTECTIVE SHIELDS THEREFOR William V. Astrup, Racine, Wis., assignor to Young Radiator Company, Racine, Wis., a corporation of Wisconsin Filed Sept. 24, 1962, Ser. No. 225,636 3 Claims. (Cl. 165134) This invention relates to the construction of coreunits for a type of heat-exchanger, commonly referred to as radiator, extensively used with high-powered engines for earth-moving equipment.

The modern construction of motor-vehicle highways involves many types of vehicular equipment for excavating, transporting and spreading earth. Much of the equipment is massive and generally powered by Diesel engines. The cooling system for such vehicular engines involves a radiator through which air is drawn by a highvelocity fan. As a rule these radiators comprise a coreunit spanning and connected to upper and lower tanks. The core-unit comprises two or more rows of transversely-staggered tubes mounting a series of closely-spaced heat-dissipating fins. The tubes usually are of elongated cross-section and disposed with their longer dimension parallel with the air stream.

The fan, driven from the engine, is arranged between the engine and the radiator to cause an air flow inwardly through the core-unit. With the vehicle constantly moving through the dust-laden air it is inevitable that the air flow through the radiator core-unit becomes highly particulated. Such air flow impinging the exposed leading edges of the front row of tubes and fins has the effect of sand blasting these tubes and fins and gradually so abrading them as to produce all-too-frequent leaks. The repair or replacement of leaking radiators is expensive not only by reason of the direct cost but also because of the indirect cost of idle equipment and workmen.

Radiator core-units of this kind usually are made of non-ferrous metals such as copper or copper alloy, primarily for the reason that it is the metal that has the highest heat-transfer capacity and corrosion-resistant ready-solderable material consistent with production costs for material and labor. However, being a comparatively soft metal it is more readily abraded than a harder metal would be. However, harder metals do not have the heat-transfer capacity of the softer metals and are more expensive in material and labor costs. Varied prior attempts to provide protection shields for the front row of these softer-metal tubes has met with limited use I01 one T838011 01 another.

The main objects of this invention therefore, are to provide an improved arrangement of protective shields for the leading edges of the front row of tubes of the conventional vehicular-radiator type of heat-exchanger subject to a particulated air-flow through the core-unit; and to provide an improved abrasion protective shield of this kind which is economical to incorporate into the manufacture of the conventional type of vehicle radiator and which has an exceedingly high endurance against abrasion by even the heaviest particulated air flow through the core-unit.

In the adaptation shown in the accompanying drawmgs:

FIG. 1 is a perspective view of a small section of coreunit wherein the leading edges of the front row of tubes are protected against abrasion by shields constructed in accordance with this invention;

FIG. 2 is an enlarged, end view of one of the protected tubes as viewed from the plane of the line 2-2 of FIG. 1;

FIG. 3 is a side view of the section of the core-unit shown in FIG. 1;

FIG. 4 is a fragmentary, front-end view of a section of the same taken on the plane of the line 44 of FIG. 3; and

FIG. 5 is a reduced, plan view of a section of a doubletube-row core-unit constructed in accordance with this invention.

The essential concept of this invention involves a conventional core-unit for a vehicle-radiator-type heat-exchanger wherein the leading edge of each of the front row of tubes is embraced in an abrasion-protective shield.

A core-unit embodying the foregoing concept comprises a battery of tubes 6 mounting a series of fins 7 with the leading edges 8 of the front row of tubes 6 embraced in protective shields 9. The fragment of coreunit shown in the drawing is illustrative of the general structural arrangement of the tubes 6 and fins 7 for a conventional core-unit for a radiator-type heat-exchanger for motor vehicles.

The tubes 6 in such a radiator, as a rule, are of flat, elongated form and arranged in staggered relationship, as indicated in FIG. 5. The ends 11 of the tubes 6 extend a suflicient distance beyond the upper and lower fins 7 to permit telescopic positioning of the tube ends in registering openings in and bonding to header plates (not here shown) for the upper and lower tanks of the radiator.

The fins 7 are formed with apertures 12 to snugly embrace the tubes 6 and are arranged in closely-spaced relationship to each other. Generally, the fins 7 are formed with flanges 13 around the tube apertures 11 to contactively embrace the tubes 6 and thereby enhance the heat-transfer facility of the tubes 6 to the fins 7. In this development, however, the front row of tube apertures 12 and the flanges 13 have the forward portions thereof enlarged to accommodate the shields 9. Preferably, though not necessarily, these enlarged portions of the front row of apertures 12 and flanges 13 are about half the length of the longer, external dimension of the tubes 6.

The shields 9, as here shown, for such elongated tubes 6, are of U-shaped form and dimensioned in width (crosswise) and depth (front to rear) to snugly embrace the leading edges 8 and the parallel sides of thetubes 6 for approximately half their longer dimension. Obviously, these shields 9 also snugly fit in the enlarged forward portions of the aligned apertures 12 and flanges 13 of the fins 7.

In length (axially of the tubes) the shields 9 are just enough less than the length of the tubes 6 to leave the tube ends 11 exposed for telescopic insertion in and bonding to the header plates (not here shown). Thus, each shield 9, in the completed core-unit, contactively embraces the exposed leading edge 8 and the exterior side faces of the forward half of the tubes 6 throughout the entire length of the tubes. Concurrently, each shield 9 is contactively embraced, through the entire length, by the inner peripheral faces of the fin apertures 12 and fin flanges 13.

Forward perimetrical portions of each fin 7 is doubled back to form a narrow, hem-like reinforcing strip 10, extending slightly rearward of the forward edge of the respective fin flange 13.

After assembly of the shields 9, the fins 7 and the tubes 6 the contacting areas of all such are solder bonded together to form a rigid, unitary core-unit structure.

As hereinbefore explained, the tubes 6 and fins 7, for such a radiator-type heat-exchanger, are formed from non-ferrous metal such as copper or copper alloy. So it is with a core-unit constructed in accordance with this invention. However, the shields 9, preferably, are

formed of a ferrous metal, such as steel, since that metal is more resistant to abrasion than is the non-ferrous metal of the tubes 6.

In use on any vehicular equipment, such as earthmoving equipment, the particulated air-flow through the core-unit, in the direction of the arrows of FIGS. 1 and 5, will impinge on the advancing edges of the shields 9 and be deflected into the air stream flow rearwardly through the core unit. The shields 9, being steel, Will Withstand the sand blasting erosion thereof for the life of the radiator as it would be in other types of service not involving such heavy particulated air-flow.

Variations and modifications in the details and structure and arrangement of the parts may be resorted to Within the spirit and coverage of the appended claims.

I claim:

1. A heat-exchanger core-unit of the class described comprising,

(a) a battery of tubes arranged in parallel relationship,

(b) an arcuate-shaped shield of continuous unbroken area throughout its entire length contactively embracing the entire periphery of the leading edge of each tube throughout substantially the entire length of the tube, and

(c) a stack of heat-dissipating fins arranged on the tubes in closely-spaced position to each other each having a series of tube openings whereby each fin contactively embraces the peripheries of the respective shield and the peripheries of the respective tubes rearwardly of the shields.

2. A heat exchanger core-unit of the class described comprising,

(a) a battery of tubes each of elongated cross-section arranged with the long dimensions parallel,

(b) an arcuate-shaped shield of U-shaped cross-section and of continuous unbroken area throughout its entire length contactively embracing the entire periphery of the leading edge and forward portions of the parallel sides of each tube throughout substantially the entire length of the tube, and

(c) a stack of heat-dissipating fins arranged on the tubes in closely-spaced position to each other each having a series of tube openings of elongated contour With the forward part conformed to the U-shaped shield and the rear part conformed to the shape of the tube, and contactively embracing the peripheries of the respective shields and the peripheries of the respective tubes rearWardly of the shields.

3. A heat-exchanger core-unit of the class described as set forth in claim 2 wherein the fins are structured with flanges disposed transversely to the plane of the fins to contactively embrace the tubes and the forward perimetrical portion of each fin is doubled back upon itself flat against one face of the fin to form a narrow, hem-like reinforcing strip embracive of the forward periphery of the respective fin flange.

References Cited in the file of this patent UNITED STATES PATENTS 1,937,343 Higgins Dec. 7, 1932 1,982,931 Schank et a1. June 17, 1933 2,795,402 Modine Jan. 13, 1951 2,853,279 Switzer Nov. 27, 1953 2,902,264 Schick et al Oct. 24, 1957 

1. A HEAT-EXCHANGER CORE-UNIT OF THE CLASS DESCRIBED COMPRISING, (A) A BATTERY OF TUBES ARRANGED IN PARALLEL RELATIONSHIP, (B) AN ARCUATE-SHAPED SHIELD OF CONTINUOUS UNBROKEN AREA THROUGHOUT ITS ENTIRE LENGTH CONTACTIVELY EMBRACING THE ENTIRE PERIPHERY OF THE LEADING EDGE OF EACH TUBE THROUGHOUT SUBSTANTIALLY THE ENTIRE LENGTH OF THE TUBE, AND (C) A STACK OF HEAT-DISSIPATING FINS ARRANGED ON THE TUBES IN CLOSELY-SPACED POSITION TO EACH OTHER EACH HAVING A SERIES OF TUBE OPENINGS WHEREBY EACH FIN CONTACTIVELY EMBRACES THE PERIPHERIES OF THE RESPECTIVE SHIELD AND THE PERIPHERIES OF THE RESPECTIVE TUBES REARWARDLY OF THE SHIELDS. 